Windscreen cleaner by The Umbilical Brothers
Shane and Dave, the Umbilical Brothers are two Australian comics specialized in making noise on the actions of the other. Often, Shane makes the noise, and Dave mime the action.
If it's not very clear, just watch the video! They are wonderful.
You may already seen them on TV with Jay Leno and David Letterman, and the video is quite popular on the Web.
This is the official website UmbilicalBrothers.com, and here is the Windscreen cleaner in video:
You can see more Umbilical Brothers's sketches on Dailymotion. These guys are so talented.